1. Field of the Invention
This invention pertains to medical suction bottle assemblies.
2. Description of the Prior Art
Medical suction bottle assemblies in general use consist of a bottle and cover which are secured together with a leak tight fit. Two connections are provided in the cover, one to be connected by hose or other means to the source of vacuum, for example, a vacuum pump or hospital vacuum outlet station, the other connection being connected by means of a hose to the particular area in a patient requiring drainage.
There is normally a float assembly in line with the vacuum source inlet that will close off same as the float rises to a predetermined level. Floats mounted on stems guided by bushing have been used, the stem having a disc or seal at the upper end to effect a shut-off of the vacuum source. In other cases the float may be enclosed in a vertical cage, the float itself acting as the plug to seal the inlet. In still other cases, flapper type shut-off valves have been used.
In all of the above cases, at the moment of shut-off a residual vacuum or negative pressure exists in the bottle. Flow will continue from the patient until this negative pressure is in balance with the atmospheric pressure less the weight of the column of fluid still in the patient.
Medically, various negative pressures are used and to avoid contamination of the suction lines the float level for shut-off must be kept low in the jar, resulting in great inefficiency of volumetric use.
Reliance on a float operated vacuum source shut-off valve alone has resulted in contamination of equipment when shut-off leakage has occurred. Hence providing an apparatus to effectively seal off the vacuum source and vent the negative pressure to conclude the drainage operation is important.